The applicant of this application has previously proposed a dual type antilock braking device of this kind in Japanese Patent Application No. 56-98976 filed on June 25, 1981. However, such a device has encountered a disadvantage as follows. In the event either one of the wheel cylinders for front and rear wheels be failed, there cannot be obtained a good balance in braking forces applied to both wheels because the other wheel cylinder in the same system continues to operate normally.